Study on Calculation Method of Comprehensive Stresses Acceleration Factor Based on Different Stress Sensitivity Analysis

The acceleration level of accelerated life test is usually expressed by acceleration factor. Acceleration factor refers to the ratio of the life under normal working stress to that under accelerated environment. The calculation of acceleration factor is the critical problem in the accelerated life test. At present, many corresponding acceleration models are established to calculate acceleration factors under single stress. However, there are few methods to calculate the acceleration factor under comprehensive stresses, especially in three or more stresses. The calculation of acceleration factor under comprehensive stresses has become a major problem in engineering. In the paper, stress sensitivity factor is introduced to characterize the contribution of different stresses to failure, and a method of calculating acceleration factor under comprehensive stresses based on sensitivity factor is proposed. The method is applied through historical failure data in order to provide theoretical guidance for calculating acceleration factor under comprehensive stresses.